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    <title>Document</title>
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    <script>
        //根据位置返回字符
        //1.chartAt(index)根据索引号返回字符
        let str = "abcdef";
        console.log(str.charAt(1));

        //2.str[index] H5 新增的
        console.log(str[0]);

        //3.charCodeAt(index)   返回相应索引号的字符ASCII 值 目的:判断用户按下哪个键
        console.log(str.charCodeAt(0));


        //4.ASCII码值转化为对应字符
        let result = String.fromCharCode(65);
        console.log(result);



        let arr = [];
        for (let i = 0; i < 91; i++) {
            let temp = String.fromCharCode(i);
            arr.push(temp)
        }
        console.log(arr);

    </script>
</body>

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